Hydroplane boat



1942- E. WADDINGTON 2,294,104

' HYDROPLANE BOAI Filed Oc't., 5, 1959 his attornegs Patented Aug. 25,1942 UiTE QFEECE Application October 5, 1939, Serial No. 298,093 InGreat Britain October 5, 1938 Claims.

This invention relates to hydroplane boats and has for itsobject toprovide improved means for the propulsion thereof.

According to the present invention there is provided on a fiat-bottomedhydroplane boat a multi-bladed impeller, the blades of which arecomposed of springy material such as tapered steel, so that they arecapable of deflecting under load with the result that the volume sweptby the impeller is correspondingly reduced. Preferably the blades areset so that they always have a rearward inclination relative to thedirection in which the impeller rotates. Further, instead of making theblades extend each in a single piece from side to side of the impellerthey may advantageously be constituted by a number of separate springtongues arranged in staggered or echelon formation so as to produce asteady propelling efiort owing to the number of impulses which areimparted to the boat for each revolution of the impeller.

Further, the invention contemplates the provision in a hydroplane boatof longitudinal ribs which are fitted to the bottom of said boat andextend substantially parallel with the main axis thereof, said ribsserving to restrict or obstruct lateral spreading of the water as theboat proceeds, thus enabling said boat to be lifted substantially ontothe surface of the water as the speed increases.

For steering purposes one or more vanes, plungers or like projectableelements can be fitted in the bottom of the boat, preferably adjacentthe stern thereof so as to operate by the drag effect which is producedwhen one or other is brought into action, said plungers or equivalentelements being capable of retraction so that the streamline form of thebottom of the boat is unimpaired.

The invention is illustrated in the accompanying diagrammatic drawing,in which Figure 1 is a side elevation of an improved bydroplane boat;

Figure 2 is a plan thereof;

Figure 3 is a side elevation to an enlarged scale showing thearrangement of the impeller; and

Figures 4, 5 and 6 are sections taken on the lines 44, 55 and 66respectively of Figure 1.

The hull of the hydroplane boat is indicated at 10 and has a flat bottomH, as will be seen in Figures 4 and 5, the sides 12 and 13 beingvertical and being arranged to taper towards the bow [4. The stern partl5 of the hull is substantially flat, and a multi-bladed impeller I6 isfitted upon a transverse shaft 19 mounted in brackets 21 and the drivingmeans.

28. An engine 29 having a driving shaft 30 is connected with the shaft19 by a totally enclosed oil bath gear box 3|, whereby the impeller isrotated in a clockwise direction, as viewed in Figure 1. The impeller isdivided transversely into short sections indicated at H in Figure 2 andeach section is provided with a number of tapered steel impeller bladesin the manner shown in Figure 3. A central hub member l8 fitted to thetransverse shaft I9 is substantially polygonal or circular in shape andis provided with a number of rearwardly inclined blades 29, the tips ofwhich normally follow a path of relatively large diameter indicated bythe dotted line 2 I, the lowest part of which lies just below the levelof the bottom I l as will be seen in Figure 1. When the boat is startingfrom rest it lies relatively deep in the Water, with the result that thelower blades 223 are well submerged. Owing to the resistance offered bythe water when the boat is getting up speed the blades 26, by virtue oftheir springy nature, are deflected rearwardly to the position indicatedby the broken lines 2311, with the result that the diameter of the sweptvolume is considerably reduced as indicated by the dotted circle 22.This of course tends to relieve the load upon Further, in order toreduce shock as much as possible, the sections ll of the impeller arearranged so that the blades 20 are staggered, as will be seen in Figure2, thus producing a very large number of small impulses for eachrevolution of the impeller. The blades 20 can taper if desired inthickness and/or Width towards their outer extremities, and may be quitepointed in shape.

When the boat is well under way the forward velocity acting upon thebottom of the hull causes the latter to be lifted practically onto thesurface of the water, with the result that only the tips of the blades20 become immersed. The peripheral speed of the impeller is however veryhigh, owing to the fact that the blades 20 assume their undeflectedposition, the blade tips following the relatively large circle 21 inFigure 3.

The bottom ll of the hull is formed or fitted with a plurality oflongitudinal ribs 23 and these largely prevent water from beingdisplaced sideways when the boat is in motion, thus ensuring that theboat will rise in the water. Steering is effected by lowering one orother of a pair of plungers or equivalent members 24 and 25 adjacent thestern [5 of the hull l0. These members when in their fully raisedposition have their lower parts flush with the bottom I I, so as topreserve the streamline form thereof, but when 10wered create drag whichmay be utilised either for rounding a turn or for bringing the boatrapidly to a standstill.

It will of course be appreciated that the invention may be applied inways other than that illustrated and that the accompanying drawing isregarded as being merely diagrammatic with a View to explaining theaction of the improved arrangement. The bending back of the steel bladeshas the following three main advantages when starting up: firstly ittemporarily reduces the depth to which the blades are immersed; secondlyit temporarily reduces the driving diameter of each set of impellerblades until the boat has gained sufficient speed to rise; and thirdlythe bending of the impeller blades under load has the effect of causingthe tips to rise vertically out of the water when starting up, saidblades however resuming their normal driving diameter when the boat hasrisen in the water and the resistance to forward progress isconsequently reduced.

I claim:

1. In a flat bottomed hydroplane vessel, a horizontal shaft transverseto the keel line of the vessel, a rear paddle wheel mounted on saidhorizontal transverse shaft, a plurality of resilient blades on saidwheel disposed at right angles to the plane of rotation of the wheel,said blades being deflected rearwardly by the resisting action of thewater when the forward rotation of the paddle wheel is started wherebythe effective diameter of the paddle wheel is reduced and its liftingaction increased, said blades being restored to their normal position offull diameter when the vessel is travelling at speed on the surface ofthe water.

2. In a flat bottomed hydroplane vessel, a horizontal shaft transverseto the keel line of the vessel, a rear horizontally mounted paddlewheel, resilient blades disposed on said wheel at right angles to theplane of rotation of the wheel and tapered towards their outerextremities whereby the blades being deflected rearwardly by theresisting action of the water on forward starting and producing amaximum lifting effect, the extent of bending of the blades decreasingas the vessel rises on the surface of the water until the full diameterof the paddle wheel is regained when the vessel is traveling at speed onthe surface of the water with only the pointed tips of the bladesdipping therein.

3. In a flat bottomed hydroplane craft, a horizontal shaft transverse tothe keel line of the craft, a horizontally mounted stern paddle wheel.blades of springy material secured to said wheel,

said blades deflecting rearwardly by the resisting action of the waterand exerting a liftin action on the rear of the vessel on forwardstarting changing to a forward propelling action when the vessel is atspeed, said paddle wheel comprising a plurality of circumferential setsof blades disposed at right angles to the plane of rotation of thepaddle wheel and the blades of each set being angularly displaced withrespect to those of the other sets, and a plurality of 10:1- gitudinalribs along the under side of the boat, forming a number of parallelunobstructed channels in the same plane, with their rear endsimmediately in front of the paddle blades to ensure that the tip of eachblade immerses to the same depth when the vessel is being driven atspeed.

4. In a flat bottomed hydroplane craft, a horizontal shaft transverse tothe keel line of the craft, a horizontally mounted stern paddle wheel,blades of spring material secured to said wheel, said blades beingdeflected rearwardly by the resisting action of the water so that thepaddle exerts a lifting action on the rear of the vessel on forwardstarting which changes to a forward propelling action When the vessel isat speed, said paddle wheel comprising a plurality of circumferentialsets of blades disposed at right angles to the plane of rotation of thepaddle wheel with the blades of each set angularly displaced withrespect to those of the other sets, and a steering device constituted bya single pair of separately operable plungers at the rear part of thevessel one on each side of the longitudinal axis thereof adapted to beprojected downwardly.

,5. In a flat bottomed hydroplane Vessel, a horizontal shaft transverseto the keel line of the vessel, a stern paddle wheel mounted on ahorizontal transverse shaft, a plurality of sets of rearwardly inclinedresilient blades on the Wheel disposed at right angles to the plane ofrotation, said blades being deflected rearwardly by the resisting actionof the water on initial forward rotation of the wheel, whereby a maximumlift ing action is obtained which gradually changes to propelling actionas the vessel rises on the surface of the water with increase of speed,driving means for operating the said transverse shaft, a plurality oflongitudinal ribs on the bottom of the vessel forming unobstructedpassageways and a single pair of rear plunger members, normally flushwith the bottom of the boat, which may be separately projecteddownwardly one on either side of the longitudinal axis of the vessel forsteering purposes.

EDWIN WADDINGTON.

